"We want an agreement at this summit, but this agreement must be fair and everyone must pay his fair share of financing enlargement," a spokesman quoted Mr Chirac as saying.

France wants to defend the EU's agricultural policy from any attempt at reform and demands the UK gives up more of the rebate it receives on its budget contribution to help pay for EU expansion.

Britain says it will offer no further concessions unless France agrees to at least allow the possibility of serious reform of agricultural policy in three years' time.

Germany's foreign minister has said he believes agreement is possible on the UK proposal.

However, German Chancellor Angela Merkel told reporters that Germany would not accept a deal "at any price".

Austrian Chancellor Wolfgang Schuessel said he believed the 25 nations were moving in the right direction towards a deal.

Angela Merkel has said she will not accept a deal "at any price"

European Commission President Jose Manuel Barroso called on EU leaders to work out a "credible" budget deal to fund the bloc's expansion into Eastern Europe.

French and Polish foreign ministers wrote in a joint letter to the Financial Times newspaper in Britain that, even after revisions submitted on Wednesday, the UK proposal could not form the basis of agreement.

The letter said the UK had championed the enlargement of the EU and should be willing to cover the costs of admitting the 10 countries that joined last year.

In theory, EU leaders have until March to hammer out a deal, but planning for long-term projects could be hurt, the BBC's Oana Lungescu in Brussels says.

The EU should carry out a comprehensive reassessment of the financial framework, covering both revenue and expenditure